CHAPTER 1
INTRODUCTION
This chapter describes the introduction of the project which titled as Traffic Light LED fault Monitoring and Detection System. The background of this project will
reveals about the traffic light, the light emitting diode LED, color blindness to the color of traffic light and the benefit of this system. Then, this chapter also will be
exposed to the problem statement, objective of this project and the scope involved.
1.1 Background
Figure 1.1: LED Traffic Light
Traffic light is very useful and important in daily path of the road user. Since people using traffic light every day, the fault of traffic light will be the critical problem
for the road user. The problem such as half broken of traffic light display will disrupt the vision of the road user. This project appears with the system which will monitor the
traffic light condition and detect the broken LED of the traffic light display.
Traffic light, which may also be known as stop light, traffic light lamps, traffic signals, stop-and-go lights, robots or semaphore are signaling devices positioned at road
intersection, pedestrian crossing and other places that suitable to control competing flows of traffic. They assign the right of way to road users by the use of lights in
standard color Red-Amber-Green such as in Figure 1.1. In a typically cycle, illumination of the green light allows traffic to proceed in the direction denoted,
illumination of the amber light denoting if safe to, prepare to stop short of the intersection, and illumination of the red signal prohibits any traffic from proceeding.[1]
Nowadays, many types of traffic light on the intersection road such as single aspect, dual aspects, three or more aspects and pedestrian or cyclist crossing lights.
Usually traffic light that can be applies to control and reduce the traffic jam at the peak time. Based on this project “Traffic Light LED Fault Monitoring and Detection System”
is powered by solar power at the daytime, charging the battery for used back up at the night time and bypass to AC power supply automatically if rainy season continuously
and there is no sunlight or enough battery [1]. This method of power supply used will be
very effectively to reduce the cost of electricity.
Light Emitting Diode LED Traffic Signals have become an efficient and effective alternative to traditional incandescent signals. The two main advantages of
LED signals are- very low power consumption 10 W to 22 W and very long life, as high as 7 to 10 years. When compared with the typical energy needs of an incandescent
bulb, which is 135 Watts, the savings resulting from the low energy usage of LED signals can be as high as 93. In addition to the low energy usage, the long life of LED
signals means low maintenance costs, which makes LED signals a worthwhile investment and also environment-friendly. [2]
Other benefits of LED signals include elimination of catastrophic failures. Unlike an incandescent bulb which has only one filament, an LED signal is made out of a
matrix of several dozen LEDs. The signal continues to function even if several of these miniature diodes stop working. On the other hand, when the filament of an incandescent
bulb fails, the display goes dark requiring immediate replacement. Besides, LED signals are brighter compared to incandescent traffic signals, which enhance intersection safety.
Furthermore, the phantom effect can be eliminated. Incandescent traffic signals use reflectors behind the bulbs. For signals on east-west approaches during morning and
evening hours, all colors seem to light up when the sunrays fall directly on these signals. This problem is eliminated when LED signals are used because there are no reflectors in
LED signals. [2]
According to Oxford dictionary, color blindness is the inability to distinguish certain colors under bright illumination. There are many types and degrees of color
blindness. It is more accurately called color vision deficiencies. The most category of color blindness is called re-green color blindness such as protanopia, protanomaly,
deuteranopia and deuteranomaly [3]. It cannot be concluded that these group of people cannot see the red or green color. They just have the difficulty in differentiating between
these two colors because not all reds and greens are distinguishable. Another problem of these people, they see red and green color as yellow, orange, and beige in color.
Therefore, they will confuse whether the color is the real yellow, orange and beige color or is the red and green color. The least affected color is the blue color. Many people do
not consider being color blind is a serious problem [4]. This is because they still can see things in this world. In fact, color blind people are classed as disability group of people.
Therefore, there is not much concern put on their situation and difficulty. Another reason is that people are concerning about the safety of these group of people especially in
traffic lights recognition. Most of the researches are done in the traffic lights applications.
Urban traffic control is a major area in which Traffic Light LED Fault Monitoring and Detection System can be applied. At the local level, traffic signals are
designed to manage vehicle conflicts at intersections, allocating time among the conflicting traffic streams which must share the use of the intersection. The logic is, the
contractor need to do the maintenance on the traffic light and replace the broken LED to a new one at the time they feel appropriate. At a higher level, maintenance of traffic
light can be part of a broader control strategy [5]. In this case, maintenance controller is used as tools for monitoring and detecting the broken LED, either in urban or rural areas,
to provide a more efficient maintenance and keep better performance to the traffic light.
The benefit of this project, it wills easier the contractor job whereby the maintenance system of the LED traffic light will be running automatically. Since this
system using current based measurement, it works when the total current of LED display achieves the threshold level. In other words, when the total current drop to 70 which is
the maximum level of proper display of traffic light, the three special LED will be flashed and the seven segments will display the number of broken LEDs. It will be very
appropriate time to replace existing traffic light with this system if some of the conventional traffic light has half broken of LED. The outcomes will be better than only
replace the LED due to the low cost in future, time saving, and maintenance system is more manageable.
1.2 Problem statement
